Unit Scenario: Ruler of the Glacier Cocytus

Non-Canon: REMINDER! This page is considered as among one of the many pure game contents found exclusive in Mass for the Dead only. It includes the new standalone characters that had a first-time appearance in the game. Meanwhile, the old characters had a different role and fate than from the main storyline in the official books. For that reason, it has no connections to the canon story materials of Overlord Light Novel series. The content that you had read here are based on the Overlord mobile game.

Unit ScenarioRuler of the Glacier Cocytus
Information
Release Date	July 31, 2021

Unit Scenario: Ruler of the Glacier Cocytus is a character scenario released in Mass for the Dead, featuring the character Cocytus.

Episode 1: Invitation

Zaryusu Shasha welcomes the protagonist, Slimeko, and Cocytus to the village of the lizardmen in the wetlands where the demi-humans are holding a feast in their honor. The former traveler encourages his guest not to be strangers as they are his people's benefactors, stating that since the incident with the Contaminated Beasts at the Great Lake, more of the lizardmen tribes have been coming together to have a gathering.

Zaryusu having been inspired by the multi-racial culture of Nazarick, he has been encouraging the same with the lizardmen to erase the tribal boundaries and unite the lizardman race. Hence, this feast is not just to honor the protagonist and his party but to allow his people to interact with other races from various tribes. The party from Nazarick are more than willing to deepen their relationship with that of Green Claw.

The lizardman also adds that he wants to thank Cocytus for the training the other day. Cocytus states to think nothing of it as Zaryusu is a excellent warrior by his own right. It honors Zaryusu to hear that and tells Cocytus that he has been teaching the younger generation of lizardmen his sword skills in hopes of passing on what he knows in posterity.

Zaryusu guides the group to where his brother, Shasuryu Shasha is waiting. As the party walks, Slimeko comments to the protagonist that the lizardman and Cocytus are pretty close to one another. The protagonist notes that Cocytus got permission to participate in the feast due to the great importance in maintaining relations with the lizardmen. Lizardman society is notably very different from human society but by no means less important and the protagonist vows to use his skills in diplomacy to carry out Nazarick's agenda.

Back in the Great Tomb of Nazarick, Momonga figures that Cocytus should have arrived at the village of the lizardmen. He permitted the Floor Guardian to attend as he saw some value in building trust in such exchanges as it was the same with business partners as a rule of thumb in his previous world. Plus for companies, "meet their business partners directly" even when technological means are available doesn't have the same effect. In particular, information can be obtained only because of conversation in a broken atmosphere is important. Momonga sees that out of all the Floor Guardians, only Cocytus is outside the tomb. If there is an emergency, there will be a few defense concerns with Cocytus's absence. He then hopes that Cocytus takes the opportunity to enjoy himself.

Shasuryu welcomes the guests to the feast, expressing his people's gratitude for accepting their invitation on behalf of Green Claw. As Cocytus humbly accepts the welcome, lizardmen with liquor and fish arrive to serve the guests. The level of lack of visible apprehension towards them as opposed in the past impresses Slimeko, which Zaryusu chuckles stating that he was telling the truth when he said that their tribe was changing little by little. As of now, there is very few people left who are wary of them. The praise falters Slimeko and it almost makes her melt. The chieftain of Green Claw bides his guests to partake in the feast which is mostly composed of raw fish.

The protagonist is happy to oblige, though the traveler is worried that his brother may have prepared too much for the feast. The diplomat has no difficulty and Slimeko can only watch stunned as her partner consumes food that would have been inedible for humans. Cocytus watching on thinks that the protagonist's excessive appetite is mostly due to his racial penalty as a homunculus.

Episode 2: Trigger

The feast continues with the lizardmen and guest enjoying the festivities. None more than Shasuryu Shasha which many of the guests and even Zaryusu take notice of. Other guests like Kyuku Zuzu and Zenberu Gugu enter into the dialogue over drinks. The two are introduced to Slimeko and the protagonist. Zenberu relates the story of how some of his tribemates from Dragon Tusk, encountered the party when they first arrived at the Great Lake. He asks about the fight, promising that the former is not disgruntle when his people lost. The chieftain though asks for a challenge, which confuses Slimeko who he is talking to, but it turns out that he directed it to Cocytus.

Though knowing defeating Cocytus is unlikely, Zenberu still wants to do so as it will be no doubt be entertaining to struggle against an unwinnable match with him. He even offers Zaryusu and Kyuku to try their hand at the challenge. Cocytus accepts the challenge and decides to arrange the bout so that it is three to one. Zaryusu seeing that Cocytus is willing to accept the fight view it as a unique opportunity decides to also join in the bout along with Kyuku as well.

The protagonist watching the proceedings believes this to be the right move by Cocytus as even though the lizardmen are weaker, this fight will display how much they have improved. Still, he hopes Cocytus remembers that he himself has not regained his levels and that while the lizardmen are no threat to them now, the current power relationship may not always continue forever. Thus, for entertainment at the banquet, Cocytus, Zaryusu and the others fought in a light mock battle.

Episode 3: Introspection

A few days after the feast, Cocytus at the 5th Floor of Nazarick, is busy training. The protagonist and Slimeko having returned from E-Rantel greet their comrade. Cocytus is happy that they have come to visit him as he needs the protagonist's advice. Recalling yesterday's fight which to Slimeko's account was spectacular victory for Cocytus. However, that is apparently what the problem is for him.

The dialogue shifts to the previous day, during the fight when Cocytus fought Zenberu, Zaryusu and Kyuku simultaneously. The three were all defeated easily by the Floor Guardian even though they all fought together as one group against one person. The victory is not the problem but on how it was achieved. In the fight, the blood of Zenberu was shed by Cocytus, but he did not mean to do so in that sort of fashion. It was only due to the lizardman's "Iron Skin" that his opponent came out unhurt. While Slimeko doesn't see much of an issue considering the wound was minor in the end, the Floor Guardian still feels he has a bit of inadequate control over his own abilities.

Cocytus amounts this as failure to be embarrassing as unplanned actions could hinder his strength. Seeing that Cocytus is taking this more serious than they had initially thought, the protagonist tries to help the warrior find the source of his failure and even suggests that the times he has been trying to regain his strength may be affecting his skills and might have been the cause for him to accidentally misuse his attack power later down the line. The Floor Guardian cannot dismiss it as a possibility as he has been exerting himself to make up for the difference in the levels he lost.

Slimeko thinks that maybe he needs to find a balance like how he was at his original level. By grasping the degree of power, it should be a bit easier to adjust for him eventually. Cocytus agrees hence why he needs a special someone to help guide him to do this. When Slimeko asks Cocytus why is he hesitant to overuse his abilities, to which the Floor Guardian responded, by blurting out the word "heir" much to her confusion and watches as he goes on a tirade of harming the successor if he cannot adeptly control himself, before the slime brings him back to his senses.

Now having something to work with, the protagonist promises to research various types of training for Cocytus; thus, beginning the start of the "hands-on" skill improvement training course for Cocytus.

Episode 4: Special Training

Slimeko and the protagonist are later seen observing Cocytus commenting on his concentration and determination. The protagonist muse that the Floor Guardian is being a bit strict with himself, as he is a person who never compromises or makes any easy choices. Once he makes up his mind, Cocytus will make sure to do it. Though the direction is different from usual, Cocytus always aims for greater heights which the protagonist believed is the secret to Cocytus's incredible strength as a powerful warrior. Slimeko agrees with the evaluation, stating that the results of the special training are gradually beginning to appear over the course of time.

Cocytus having taken in the protagonist's suggestions began using various low level skeletons to accurately adjust his power output for better control. While he trains with the undead, Narberal Gamma arrives having heard rumors of what Cocytus is doing. Slimeko explains to the maid about the purpose of Cocytus's training session against the undead originating from the E-Rantel's Cemetery. This training is to prepare him when Nazarick's heir arrives when it is needed for someone like Cocytus to teach him the way of the sword.

Now understanding what is going on with Cocytus, Narberal states that since she is a creation of Nishikienrai who was a close ally to Cocytus' creator, Warrior Takemikazuchi she should be able to assist him on his endeavors. The protagonist does not see that as a problem, though asks the maid to clarify with Albedo and Shalltear Bloodfallen beforehand for permission just in case.

Episode 5: Success

Cocytus continues his matches with the undead. However while thinking of restraining himself, one of the undead ask if he is alright. Shaken by the voice, Cocytus stares at the skeleton as it begins to ask for the Floor Guardian to teach him a bit of his swordplay. The Floor Guardian does so but accidentally injures the undead along the way. Some work is still needed for Cocytus to be more gentler and aware of his strength. However, he eventually find his comfort level and manages to teach the undead swordplay. Cocytus states that perhaps the heir will be more easier to manage and train with compared to the skeletons he is using.

The voice of the skeleton turns out to be from Narberal who was throwing her voice while invisible. She reveals herself to her to Cocytus explaining that she wanted to test her acting skills that she learned from Solution Epsilon and was using a script by Demiurge. Narberal apologizes for the deception until now as the former thought she was helping Cocytus in preparing his role of teaching the successor. Cocytus is deeply touched by the action as his colleagues went out of their way to involve themselves with him.

They deemed their actions a success and Cocytus then asks permission to get rid of the undead, which Slimeko states that it would be fine as the undead were originally from outside Nazarick to begin with. However after some thought, Cocytus instead decides to freeze it using his powers under Momonga's permission and store it in the Frozen Prison out of sentimental value.

Trivia

• This is the second story unit of Cocytus in Mass for the Dead.